How to write a simple number input field?

[fgatti675]

I would like to use slate to be able to highlight parts of an input.
One of the use cases is a simple number input.
Basically a single piece of text that satisfies /^\d+(\.\d+)?$/
I have spent the past 4 hours trying different approaches and haven't found a good solution.
Can someone please point me to the right direction?
Thank you